The present invention relates generally to snowplow apparatus, and more particularly to commercial snowplow attachments for vehicles such as trucks, tractors or skid steers and any loader mounted vehicle.
Snowplows are well known apparatus for clearing snow from ground surfaces such as roadways, driveways, parking lots or other areas as desired. Snowplows are typically mounted on a vehicle and are either pushed or pulled to remove snow. For example, U.S. Pat. Nos. 5,392,538 and 4,907,357 disclose snow removal trucks having two separate snowplows including one plow on the front for pushing snow and second plow on the rear end for pulling snow. The provision of two separate snowplows on a truck is undesirable for a variety of reasons, including the extra expense necessary for providing and maintaining the plows and for practical reasons in that an operator cannot keep his eye on both plows at the same time which is potentially hazardous. U.S. Pat. No. 5,724,755 discloses a snow pusher that attaches to the bucket of a skid steer loader. Each of these aforementioned patents demonstrate that the highly desirable provision of side plates arranged on the opposite ends of a snowplow for increasing the volume of snow engaged by the snowplow. In particular, the side plates serve the function of containing the snow therebetween in front of the blade such that the snow continues to be engaged by the snowplow and does not escape out the sides.
One problem with these and other snowplows is that they are unable to easily get up close to permanent structures such as buildings for snow removal. For example, once snow is pushed up close to a building or other structure it is often very difficult if not impossible to remove that pushed snow other than manually or with another snow removal device. Moreover, the side plates increase the difficulty of locating the blade close to permanent structures and removing snow close to permanent structures.
It is an objective of the present invention to provide a snowplow apparatus that more effectively or more efficiently removes snow.
In that regard, it is a further objective to provide a snowplow apparatus that is able to more effectively remove snow next to permanent structures while retaining the ability to move a high volume of snow if so desired.
In accordance with these and other objectives, the present invention is directed towards a snowplow attachment for mounting to the front end of a vehicle such as a truck or skid steer or front end loaders of any kind that includes both a push blade (operable during forward movement of the vehicle) and a pull blade (operable during reverse movement of the vehicle). Importantly, the pull blade drops down in front of the push blade such that snow can easily be pulled back. It is an advantage that the snowplow can easily get up close to permanent structures such as buildings and remove snow therefrom even after pushing snow up close to the permanent structure. During the push mode, the pull blade is raised to avoid interference with pushed snow. The snowplow can include the desirable side plates located on the ends of the blades for containing the snow and prevent snow from escaping out the sides, thereby increasing the volume of snow moved by the plow during one sweep.
According to one embodiment of the present invention, the snowplow includes a push blade assembly that is adapted to mount directly on the vehicle and a vertically movable pull blade carried by the push blade assembly. The pull blade is maintained in a raised position during the push mode but is lowered when it is desired to go into pull mode and reverse the direction of the vehicle. The pull blade may be raised or lowered manually or by an actuator such as a fluid powered cylinder or electrical actuator such as a ball screw.
According to another embodiment of the invention, separate push blades and pull blades are arranged at separate generally fixed locations on the attachment such that the entire attachment pivots to alternatively locate one of the blades close to the ground for selecting between pushing or pulling modes. In this embodiment the pull blade similarly drops down in front of the push blade such that previously pushed snow can be pulled back. This embodiment can utilize the existing hydraulic pump of a skid steer or other loader tractors to switch between pushing and pulling modes, or can be mounted on a separate frame and pivoted by an additional actuator between pushing and pulling modes. This type of snowplow can have an attach mechanism on its back such as a quick attach mechanism common to skid steer loaders or pin on connections/attachments that are common to more conventional loader tractors.
Other objects and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.